Two persons are holding a rope of negligible mass horizontally. A 20 kg mass is attached to the rope at the midpoint; as a result the rope deviates from the horizontal direction. The tension required to completely straighten the rope is (g= 10m/s2)

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Q: 10 (CDS-II/2018)
Two persons are holding a rope of negligible mass horizontally. A 20 kg mass is attached to the rope at the midpoint; as a result the rope deviates from the horizontal direction. The tension required to completely straighten the rope is (g= 10m/s2)

question_subject: 

Logic/Reasoning

question_exam: 

CDS-II

stats: 

0,2,13,10,3,0,2

keywords: 

{'rope': [0, 0, 1, 1], 'tension': [0, 0, 0, 1], 'kg mass': [0, 0, 1, 1], 'negligible mass': [0, 0, 0, 1], '10m': [0, 0, 0, 1], 'persons': [4, 4, 9, 10], 'horizontal direction': [0, 0, 2, 2]}

The correct answer for this question is option 4, which states that the tension required to completely straighten the rope is infinitely large.

When a 20 kg mass is attached to the rope at the midpoint, it creates a downward force due to gravity. This force causes the rope to deviate from the horizontal direction. In order to completely straighten the rope, the tension in the rope needs to be equal to the weight of the hanging mass.

By using Newton`s second law of motion (F = m * a), we can calculate the weight of the hanging mass by multiplying its mass (20 kg) with the acceleration due to gravity (10 m/s^2). The weight of the hanging mass comes out to be 200 N.

Therefore, in order to completely straighten the rope, the tension in the rope should be equal to 200 N. However, as per the given options, the correct answer is option 4, which states that the tension required is infinitely large.

This means that the tension required to completely straighten the rope cannot be achieved in a practical sense, as it would need to be infinitely large.